Bed frames are commonly used devices to support a boxspring and a mattress position on top of the boxspring. These bed frames are typically made of steel angle irons that are welded or connected together by various types of connecting devices. A typical connecting device is disclosed in U.S. Pat. No. 5,161,268, where the cross bars of a bed frame have their ends attached by a lever device that detachably holds the cross bars in the desired physical arrangement.
This invention has several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this invention as expressed by the claims that follow, its more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled, xe2x80x9cDETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT,xe2x80x9d one will understand how the features of this invention provide its benefits, which include, but are not limited to, a low cost, easy to manufacture, and convenient connector system for beds frames.
The first feature of the support frame of this invention is that it uses the weight of the boxspring it is supporting to maintain in an attached condition segments of cross bars for the frame. Specifically, the bed frame includes first and second parallel side rails. Preferably, each side rail has an L-shaped configuration and each has attached thereto spaced apart first and second cross bar segments. The side rails are adapted to be coupled together by connecting their respective aligned cross bars segments together by laterally moving the cross bars together with respect to each other. The boxspring has a predetermined width and the cross bar segments, upon assembly, have a predetermined length that is substantially equal to the width of the boxspring.
The second feature is that each cross bar segment on each side rail has an inner end connected to this one side rail and an outer end. The outer ends of the first and second cross bar segments of the first side rail are adapted to be attached to the outer ends of the first and second cross bar segments of the second side rail upon alignment of these segments. The cross bars segments extend outward from the side rails at a right angle and are positioned opposed each other and aligned so that, when these outer ends are connected together, the support frame is formed. Preferably, the inner ends of the cross bars are pivotally connected to the side rail to which they are attached. Each cross bar segment has near its outer end a connection section. One connection section of one of the aligned and opposed cross bars overlies the connection section of the other cross bar segment to which it is connected.
The third feature is that a locking element is formed in one connection section and extends inward from this connection section and is positioned at a predetermined location to be received in a receptacle in the outer end of the cross bar segment to which it is opposed and connected when said cross bar segments are attached to each other. Consequently, upon placing the boxspring on the assembled support frame, the boxspring bears down on the locking element to tend to maintain this locking element in the receptacle. The locking element and the receptacle in which the locking element is received have substantially the same shape and size. Thus, when the locking element and receptacle are aligned and positioned to be coupled, the locking element fits snugly in the receptacle and is wedged in position. Preferably, each receptacle is a hole in one of the connection sections. In the preferred embodiment, the locking element overlies the receptacle and projects inwards towards the receptacle at an angle of from about 30 to about 60 degrees. This preferred locking element has a ramp surface. The locking element faces in a direction so that the ramp surface facilitates disconnection of the cross bar segments when the segments are moved towards each other. Moreover, the locking element preferably has spring action and goes into compression during connection of the cross bar segments when the segments are moved away from each other.
The forth feature is that one of the cross bar segments has at least one connector member extending from a side wall and the other cross bar segment to which said one cross bar segment is connected has a slot, typically key shaped, in a side wall that receives the connector member when the cross bar segments are connected. Preferably, the cross bar segments have an L-shaped configuration, with one leg of the L-shaped structure forming a top wall and the other leg of the L-shaped structure forming the side wall of a predetermined thickness. The connector member in the one cross bar segment has an enlarged head and a coupling member extending into and through the slot in the side wall of the other cross bar. This enables the connector member to move reciprocally in the slot between a connection position in a restricted portion of the slot and a disconnect position in an enlarged portion of the slot. The coupling member has a length substantially equal to the thickness of the side wall through which it extends, and the slot is positioned so that, during connection, the underside of the top wall of the overlying segment is pulled tightly against the upper side of the underlying segment. This causes the locking element to go into compression. When in registration with the receptacle, the locking element is forced into the receptacle by the spring action of this locking element. In the connection position, the restricted open portion of the slot is of a size that prevents the enlarged head from passing there through, and in the disconnect position, the enlarged open portion of the slot is of a size that enables the enlarged head to pass there through.
The fifth feature is that each cross bar segment has in its top wall near its outer end a connection section made of a malleable material. The locking element and the receptacle are formed by punch pressing in the malleable material in their respective connection sections.
This invention also includes a method of supporting on a support frame a boxspring with a predetermined width, including
(a) providing a support frame for the boxspring including
a pair of side rails adapted to be attached together by at least one pair of cross bars,
each cross bar having two segments that have outer ends, said two segments being adapted to be aligned with their outer ends placed into an overlapping and abutting relationship,
the outer end of one of the two segments, with an inwardly extending locking element formed in said outer end of said one segment, and the outer end of the other aligned segment having a receptacle therein,
said locking element being at a predetermined location to be received in the receptacle in the outer end of the other segment so that the distance between the attached side rails is substantially equal to the width of the box spring,
(b) manually moving the two segments of each pair of cross bars into an overlapping relationship,
(c) positioning said locking element in one section into the receptacle in the aligned opposed segment, and
(d) placing the boxspring on the bed support between the side rails, with the boxspring bearing down on the locking element to tend to maintain said locking element in said receptacle.